—but I'll give you two.
One, create a system of filing joint returns for families. That reduces the compliance burden and gets rid of a lot of other tax problems, such as attribution.
Two, make mortgage interest tax deductible. You're already taxing the interest in the bank's hands. Promote home ownership, which will help, in turn, promote productivity in building and construction and make us competitive with our neighbours to the south, who can buy homes a lot easier than we can.